Entanglement improvement via a single-side squeezing-based quantum scissors

Area of Science:

• Quantum Physics
• Quantum Information Science

Background:

• Quantum entanglement is a fundamental resource for quantum information processing.
• Two-mode squeezed vacuum states (TMSV) are crucial for generating entanglement.
• Quantum scissors (QS) are tools for manipulating quantum states, including entanglement.

Purpose of the Study:

• To theoretically investigate entanglement improvement using a single-side quantum scissors (SSQS) with local squeezing and asymmetric beam splitters (BSs).
• To explore the impact of local squeezing parameters and BS transmissivity on entanglement enhancement.
• To assess the robustness of the proposed scheme against photon loss.

Main Methods:

• Theoretical analysis of quantum entanglement.
• Application of a single-side quantum scissors (SSQS) to a two-mode squeezed vacuum state (TMSV).
• Inclusion of local squeezing operations and two asymmetrical beam splitters (BSs).

Main Results:

• Entanglement gain is significantly enhanced by increasing the local squeezing parameter, though success probability decreases.
• Entanglement can be further improved by adjusting local squeezing or BS transmissivity in a small initial squeezing region.
• The scheme demonstrates robustness against photon loss in TMSV, with local squeezing enhancing the improvement effect.

Conclusions:

• Squeezing-based SSQS at the single-photon level effectively improves quantum entanglement.
• Asymmetric BSs contribute positively to entanglement improvement in both ideal and realistic scenarios.
• The proposed method holds potential for applications in quantum communication due to enhanced entanglement.